In recent years, CCS (Carbon dioxide Capture and Storage) has been drawing attention as a technology for reducing carbon dioxide emission. CCS is a technology for selectively separating carbon dioxide from a to-be-treated gas containing carbon dioxide, capturing the separated carbon dioxide, and storing the captured carbon dioxide in the ground or water. CCS is expected to be adopted by large-scale carbon dioxide emission sources such as thermal power plants and oilfields. CCS is also applicable to carbon dioxide concentration adjustment in enclosed residential space (see Patent Literatures 1 and 2, for example).
Patent Literature 2 discloses a carbon dioxide separating and capturing apparatus adopting a solid-adsorbent method for separating and capturing carbon dioxide. The carbon dioxide separating and capturing apparatus includes an adsorbing material-packed tank packed with a solid carbon dioxide adsorbing material. The adsorbing material-packed tank is connected to piping for taking in a to-be-treated gas and piping for taking in a heating gas. The upstream end of such heating gas supply piping is connected to a steam generator. Steam generated by the steam generator is utilized as the heating gas.
According to the carbon dioxide separating and capturing apparatus, when the to-be-treated gas is supplied to the adsorbing material-packed tank, the carbon dioxide adsorbing material adsorbs and removes carbon dioxide from the to-be-treated gas, and thereby a clean gas with a lowered carbon dioxide concentration can be produced. When the steam is supplied to the adsorbing material-packed tank instead of the to-be-treated gas, the carbon dioxide adsorbing material is heated. As a result, carbon dioxide is desorbed from the carbon dioxide adsorbing material and the desorbed carbon dioxide can be captured, and also, the carbon dioxide adsorbing material can be regenerated.